JP2005201386A - Resin joint and piping method of resin-made tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin joint suitable for forming piping in which a prescribed resin-made tube is employed, and a piping method suitable for piping by utilizing a prescribed resin-made tube for piping forming. <P>SOLUTION: A resin joint 1, 2 utilized to form piping in which a prescribed resin-made tube T is employed, consists of hollow joint bodies 5, 7 formed in a prescribed shape, and of one or more cylinder members 6, 8 in which their one ends are welded to the joint bodies 5, 7 and the other ends are protruded from the joint bodies 5, 7. The cylinder members 6, 8 are made of resin having melt flow rate 0.5-1.5 times that of the tube T. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a resin joint and a piping method for a resin tube.

  Fluororesin has excellent heat resistance, chemical resistance, and electrical insulation, and is widely used in the chemical industry, the electric / electronic industry, and the like. In particular, in the semiconductor manufacturing industry which has been remarkably developed in recent years, it is frequently used for each part used in a process requiring chemical resistance such as being in contact with a chemical solution. There are a wide variety of product shapes, and in terms of cost, it has become essential to join parts in order to manufacture at a lower cost, and the dimensional accuracy has become more severe. In order to cope with this situation, preheating is not required, the contact area is large, the relative rotation speed can be increased, burrs are not generated on the inner surface of the tube part, and the fluorine resin has a high melting point. Patent Document 1 discloses a method and apparatus for welding fluororesin parts that can be welded in a short time even if different types of fluororesins are used.

When forming a pipe using a pipe forming tube made of a predetermined resin, a resin joint made of the same material as that of the tube is used, and the resin joint and the tube are welded at a predetermined position.
JP 2002-17727200 A

  The inventors of the present application have obtained the following knowledge about the conventional piping method. That is, when taking a PFA tube and a PFA joint as an example, when the PFA tubes are welded to each other, a clean joining portion is obtained. Compared to the case, there is a problem that large protrusions occur on the inner and outer surfaces of the joint side portion. This is because the PFA tube and the PFA joint are made of the same material, but the PFA tube is made of a material having low fluidity (melt flow rate) and the PFA joint is made of a material having high fluidity.

  An object of the present invention is to perform piping using a suitable resin joint for forming a pipe using a tube made of a predetermined resin and a pipe forming tube made of a predetermined resin based on the above knowledge. It is to provide a piping method suitable for the case.

  A resin joint according to the present invention is a resin joint used for forming a pipe using a tube made of a predetermined resin, and has a hollow joint body molded into a predetermined shape, and one end portion of the joint body. And at least one cylindrical member whose other end protrudes from the joint body, and the cylindrical member is made of a resin having a melt flow rate of 0.5 to 1.5 times the melt flow rate of the tube. It is characterized by this.

  The resin that forms the joint body and the cylindrical member is not particularly limited, but includes a tetrafluoroethylene-fluoroalkyl vinyl ether copolymer resin (hereinafter referred to as “PFA”), a tetrafluoroethylene-hexafluoropropylene copolymer resin ( Hereinafter referred to as “FEP”), ethylene tetrafluoride-ethylene copolymer resin (hereinafter referred to as “ETFE”), vinylidene fluoride resin (hereinafter referred to as “PVDF”), trifluoroethylene chloride resin (hereinafter referred to as “PCTFE”). And fluororesins such as modified PTFE are particularly preferred. The resin of the joint body and the resin of the cylindrical member may be different resins or the same resin. In the case of the same resin, the melt flow rate may be the same or different.

  For the cylindrical member to have a melt flow rate 0.5 to 1.5 times the melt flow rate of the tube, it is optimal that the cylindrical member is made of the same material as the tube, and the cylindrical member is the same as the tube. It means that those having basically the same composition and different melt flow rates in the range of 0.5 to 1.5 times can be preferably used.

  In order to weld the joint body and the cylindrical member, for example, the apparatus and method described in Patent Document 1 described above may be used, but the invention is not limited thereto.

  The shape of the joint body is not particularly limited, and an appropriate shape is selected according to the configuration of the pipe at the place where the joint is used.

  The joint body may be, for example, for forming a flange portion on a pipe forming tube. In this case, the cylindrical member is welded only to the other end side of the joint body having a short cylindrical shape. The inner diameter of the joint body may be made equal to the outer diameter of the cylindrical member, and the inner diameter of the joint body is made smaller than the outer diameter of the cylindrical member, and the end of the cylindrical member is fitted into the inner diameter of the joint body. An annular recess may be formed. In the former case, the inner peripheral surface of the joint main body and the outer peripheral surface of the cylindrical member are welded. In the latter case, the concave peripheral surface of the joint main body and the outer peripheral surface of the cylindrical member end, and / or the concave bottom surface of the joint main body and the cylinder. The member end face is welded. In the latter case, the inner diameter of the cylindrical member may be larger than, equal to, or smaller than the inner diameter of the joint body. More preferably they are equal.

  Further, the joint body may be formed in an L shape, a T shape, or a cross shape. In these cases, the cylindrical member is welded to the opening of the joint body.

  Moreover, the joint main body is formed into a hollow cubic shape, for example, and through holes are formed in 2 to 4 of the 6 surfaces, and a cylindrical member is welded to the edge of the through hole. Sometimes. The joint body may be a hollow polyhedron or a spherical body other than a cube. In this case, a plurality of through holes are formed so as to be arranged in an L shape, a T shape, a cross, and the like. A cylindrical member is welded to the edge.

  It is preferable that the joint body is an injection molded product or a cut product, and the cylindrical member is an extruded material. By making the joint body an injection-molded product or a machined product, the required joint body shape can be easily obtained, and by using the cylindrical member as an extruded material, a cylindrical member having excellent durability can be obtained at low cost. be able to. The injection molded product includes, for example, a product obtained by cutting the seal portion after injection molding, and the cut processed product is subjected to cutting on a molded product (non-injection molded product) such as compression molding or extrusion molding. Things shall be included.

  The joint body is preferably made of PFA resin having a melt flow rate of 10 to 20 g / 10 min, and the cylindrical member is preferably made of PFA resin having a melt flow rate of 1 to 5 g / 10 min. The melt flow rate and flex life (folding strength) are inversely proportional, with the joint body emphasizing fluidity during molding, setting the melt flow rate higher, and the cylindrical member emphasizing durability. Thus, by setting the melt flow rate to be small, it is possible to obtain a resin joint having a balance between moldability and durability.

  When the piping method of the resin tube according to the present invention is to form a pipe using a pipe forming tube made of a predetermined resin, the same resin tube as the pipe forming tube is cut to a predetermined length, Next, one end of the cut tube is welded to a hollow joint body molded into a predetermined shape, and then the other end of the cut tube is welded to one end of the pipe forming tube. .

  In the above piping method, when welding one end of the cutting tube to the joint body, by rotating at least one member, the members are welded to each other by frictional heat generated on the contact surfaces of both members, and the cutting tube When the other end is welded to the pipe forming tube, it is preferable that the ends of both members are heated and melted, and the melted ends are welded together. When welding one end of the cutting tube to the joint body, it is preferable to use rotary friction heat welding, which allows different materials to be neatly welded. When welding the other end of the cutting tube to the pipe forming tube, the same material is used. Because it is welded between each other, welding after end heating with excellent workability in the field is suitable, and this combination efficiently forms a pipe that does not have a place that becomes a liquid pool or a place that narrows the flow path. can do.

  According to the resin joint of the present invention, the hollow joint body formed into a predetermined shape, and at least one cylindrical member having one end welded to the joint body and the other end protruded from the joint body, the cylindrical member Is made of a resin having a melt flow rate of 0.5 to 1.5 times the melt flow rate of the tube, so that the welding parts are deformed in the same degree when the cylindrical member and the pipe forming tube are welded. Accordingly, the inner surface and the outer surface of the weld bead portion are not protruded, thereby eliminating the location where the liquid pool is accumulated and the location where the flow path is narrowed in the completed pipe.

  According to the resin tube piping method of the present invention, one end of a cutting tube is welded in advance to a hollow joint body molded into a predetermined shape, and then the other end of the cutting tube is connected to one end of a pipe forming tube. The welded parts are deformed at the same level when welding the cutting tube and the pipe forming tube, so that the inner and outer surfaces of the welded bead are not protruded. In this case, it is possible to eliminate a place where a liquid pool is accumulated and a place where a flow path is narrowed.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, the left and right refer to the left and right in the figure.

  FIG. 1 shows a first embodiment of a resin joint according to the present invention. An annular shape fitted to a left resin joint (1), a right resin joint (2), and a right resin joint (2). The male screw member (3) and the cap nut (4) fitted from the left resin joint (1) side and screwed to the screw member (3) constitute a resin joint assembly.

  The left resin joint (1) is formed by welding a flange (5) as a joint body and a cylindrical member (6). The right resin joint (2) is formed by welding a flange (7) as a joint body and a cylindrical member (8). An annular recess (5a) is formed on the right surface of the flange (5) of the left resin joint (1), and this recess (5a) is formed on the left surface of the flange (7) of the right resin joint (2). ) To form a ring-shaped convex portion (7a).

  The male screw member (3) and the cap nut (4) are made of resin or metal.When the cap nut (4) is tightened against the male screw member (3), the male screw member (3) Push the right side of the flange (7) of the plastic joint (2) to the left, and the cap nut (4) pushes the left side of the flange (5) of the left resin joint (1) to the right. The resin joints (1) and (2) are brought into close contact with each other in a state where the concave portions (5a) and the convex portions (7a) of the flanges (5) and (7) are fitted.

  The flanges (5) and (7) of the left and right resin joints (1) and (2) are made of PFA resin and injection molded. The flanges (5) and (7) of the left and right resin joints (1) and (2) may be made of PFA resin and cut. The cylindrical members (6) and (8) of the left and right resin joints (1) and (2) are made of PFA resin and extruded, and have the same diameter as the tube (T) used throughout the entire pipe and melt. It is made of the same material including the flow rate. Regarding the melt flow rate, the flanges (5) and (7) are 14 g / 10 minutes (preferable range is 10 to 20 g / 10 minutes), and the cylindrical members (6) and (8) are 2 g / 10 minutes (preferable range is 1-5 g / 10 min). The melt flow rate of the cylindrical members (6) and (8) is optimally the same as that of the tube (T) to which the cylindrical members (6) and (8) are welded, but 0.5 to 1 of the melt flow rate of the tube (T). A preferable range is up to 5 times.

  When obtaining the left resin joint (1), as shown in FIG. 2, a PFA cylindrical member (6) having a rod (11) for preventing torsion inserted beforehand is inserted into a PFA flange (5) and welded. The cylindrical member (6) is firmly held by using the chuck (13) provided on the stationary hollow body (12) of the machine, and the flange is formed by using the chuck (15) provided on the rotating shaft (14) side of the welding machine. Hold (5) firmly, drive the rotating shaft (14) to rotate the flange (5), and weld the flange (5) and the cylindrical member (6) by frictional heat generated on their contact surfaces As a product, a resin joint (1) (same for the right resin joint (2)) is obtained. Here, if the flange (5) is uniformly and firmly held in the circumferential direction by the chuck (15), the pressure unevenness of the flange (5) and the cylindrical member (6) is eliminated, so that the welding can be performed uniformly and the welding strength is increased. It is improved and more preferable. Examples of the chuck (15) for uniformly applying pressure in the circumferential direction include a collet chuck and a three-jaw chuck formed so as to substantially cover the circumferential direction. In addition, if the rod (11) is inserted inside the cylindrical member (6), it is easy to apply pressure between the cylindrical member (6) and the rod (11) when rotating, and strong welding can be achieved in a short time. More preferable. In FIG. 2, the cylindrical member (6) is fixed and the flange (5) is rotated. However, the fixed side and the rotating side may be reversed.

  In the first embodiment described above, the end faces of the flanges (5), (7) and the cylindrical members (6), (8) are preliminarily formed in a predetermined seal shape, and their axial relative positions are positioned and welded. Of course, after welding the flanges (5) and (7) and the cylindrical members (6) and (8), the end faces of the resin joints (1) and (2) should be machined so as to have a predetermined seal shape. It may be.

  1 and 2, the inner diameters of the flanges (5) and (7) as the joint body are equal to the outer diameters of the cylindrical members (6) and (8). ) (8) and an annular cylindrical member insertion recess having an outer diameter equal to the outer diameter of the cylindrical member (6) (8) is formed at the end of the flange. The flanges and the cylindrical members (6) and (8) may be welded in a state where the end portions of the cylindrical members (6) and (8) are fitted into the flanges.

  FIG. 3 shows a second embodiment of the resin joint of the present invention. Each of the resin joints (1) and (2) includes a flange (5) (7) as a joint body and a cylindrical member (6) (8). ) Are welded to each of the resin joints (1) and (2) of the first embodiment. The difference from the first embodiment is that the inner diameters of the flanges (5) and (7) are made equal to the inner diameters of the cylindrical members (6) and (8), and the flange (5) of the left resin joint (1). On the left surface, there is formed a recess (5b) having a peripheral surface having a diameter equal to the outer diameter of the cylindrical member (6) and into which the right end of the cylindrical member (6) is fitted, and the right resin joint (2) The right surface of the flange (7) is formed with a recess (7b) having a peripheral surface having a diameter equal to the outer diameter of the cylindrical member (8) and into which the left end of the cylindrical member (8) is fitted. It is. As in the first embodiment, an annular recess (5a) is formed on the right surface of the flange (5) of the left resin joint (1), and the left surface of the flange (7) of the right resin joint (2). Is formed with an annular convex portion (7a) to be fitted into the concave portion (5a).

  The flanges (5) and (7) of the left and right resin joints (1) and (2) are made of PFA resin and are injection molded products or cut products. The cylindrical members (6) and (8) of the left and right resin joints (1) and (2) are made of PFA resin and extruded, and have the same diameter as the tube (T) used throughout the entire pipe and melt. It is made of the same material including the flow rate. Regarding the melt flow rate, the flanges (5) and (7) are 14 g / 10 minutes (preferable range is 10 to 20 g / 10 minutes), and the cylindrical members (6) and (8) are 2 g / 10 minutes (preferable range is 1-5 g / 10 min). The melt flow rate of the cylindrical members (6) and (8) is optimally the same as that of the tube (T) to which the cylindrical members (6) and (8) are welded, but 0.5 to 1 of the melt flow rate of the tube (T). A preferable range is up to 5 times. The joint bodies (5) and (7) of the resin joints (1) and (2) and the cylindrical members (6) and (8) are welded by the same method as shown in FIG.

  FIG. 4 shows a third embodiment of the resin joint of the present invention. This resin joint (21) is a T-shaped joint, and cylindrical members (23), (24), and (25) are welded to respective openings of a joint body (22) having a T-shape. The inner diameter of the joint body (22) is made smaller than the outer diameter of the cylindrical members (23), (24), and (25), and the cylindrical members (23) (24) ( An annular cylindrical member insertion recess having an outer diameter equal to the outer diameter of 25) is formed, and in the state where the ends of the cylindrical members (23) (24) (25) are inserted into the recess, the joint The main body (22) and the cylindrical members (23), (24), and (25) are welded.

  The joint body (22) of the resin joint (21) is made of PFA resin and is an injection molded product or a cut product. Each cylindrical member (23) (24) (25) is made of PFA resin and is an extruded material, and has the same diameter as the tube (T) used throughout the piping and the same material including the melt flow rate. Has been. Regarding the melt flow rate, the joint body (22) is 14 g / 10 minutes (preferable range is 10 to 20 g / 10 minutes), and the cylindrical members (23), (24) and (25) are 2 g / 10 minutes (preferable range). 1-5 g / 10 min). The melt flow rate of the cylindrical members (23), (24), and (25) is optimally the same as that of the tube (T) to which the cylindrical members (23), (24), and 25 are welded. The preferred range is 5 to 1.5 times. The joint body (22) of the resin joint (21) and the cylindrical members (23), (24), and (25) are welded by the same method as shown in FIG.

  In addition, as a coupling main body of this embodiment, in addition to T shape, L shape, a cross shape, etc. are possible.

  FIG. 5 shows a fourth embodiment of the resin joint of the present invention. In this resin joint (31), through holes (32a) and (32b) are formed in two of the six faces of the joint body (32) formed as a hollow cube, and a cylindrical member (33) is formed at the edge of the through hole. (34) are welded to each other.

  The joint body (32) of the resin joint (31) is made of PFA resin and is an injection molded product or a cut product. Each of the cylindrical members (33) and (34) is made of PFA resin and is an extruded material, and has the same diameter as that of the tube used throughout the piping and the same material including the melt flow rate. Regarding the melt flow rate, the joint body (32) is 14 g / 10 minutes (preferable range is 10 to 20 g / 10 minutes), and the cylindrical members (33) and (34) are 2 g / 10 minutes (preferable range is 1 to 10 minutes). 5 g / 10 min). The melt flow rate of the cylindrical members (33) and (34) is optimally the same as the tube to which it is welded, but is preferably 0.5 to 1.5 times the melt flow rate of the tube. It is a range. The joint body (32) of the resin joint (31) and the cylindrical members (33) (34) are welded by the same method as shown in FIG.

  In addition, in the resin joint of this embodiment, it is possible to obtain various types by appropriately selecting the number of through holes from 2 to 4 and appropriately selecting the surface to be opened. Further, the shape of the joint body may be a polyhedron other than a cube (regular hexahedron) or a spherical body.

  The resin joint obtained as described above is used as follows when a pipe is formed using a pipe forming tube made of a predetermined resin.

  That is, the same resin tube as the pipe forming tube (T) is cut to a predetermined length to form cylindrical members (6) (8) (23) (24) (25) (33) (34), A hollow joint body (5) (7) (22) in which one end of the cylindrical member (cut tube) (6) (8) (23) (24) (25) (33) (34) is formed into a predetermined shape ) (32) to form resin joints (1), (2), (21), and (31) in advance, after which the plastic joints (1), (2), (21), and (31) cylinder What is necessary is just to weld the other end part of member (cutting tube) (6) (8) (23) (24) (25) (33) (34) with the one end part of the tube for tube formation (T).

  Here, since it is difficult to rotate one of the resin joints (1), (2), (21), and (31) and the tube (T), the welding method and apparatus shown in FIG. 6 are used. Ends of cylindrical members (6) (8) (23) (24) (25) (33) (34) of plastic joints (1) (2) (21) (31) and pipe forming tubes (T) It is preferable that welding is performed by heating and melting the end portions of the two and abutting the melt end portions.

  In FIG. 6, the synthetic resin tubular members are welded to each other by joining a pair of clamp members (41) and (42) to the end of a cylindrical member (reference numeral T 1) of a plastic joint and a pipe forming tube (reference numeral Each of the members (T1) and (T2) is heated and melted by the end surface heater (43) (FIG. (B)). Next, after removing the end surface heater (43), the clamp member (42) supported by the movable-side clamp holding means (45) slides, and the pipe forming tube (T2) held by this is melted. The end portion is butted against the molten end portion of the cylindrical member (T1) of the resin joint held by the clamp member (41) supported by the fixed-side clamp holding means (44) (FIG. (C)). This is done by cooling.

  Thus, the resin joints (1), (2), (21), and (31) and the pipe forming tube (T) can be efficiently welded at the piping site.

  The resin joints (1), (2), (21), and (31) may be welded with the same joints or with different joints, but this joint (1) (2) (21) (31) cylinder The welding of the members (6), (8), (23), (24), (25), (33), and (34) is the same as the welding of the cylindrical member (T1) and the pipe forming tube (T2) shown in FIG. Can be done.

It is sectional drawing which shows 1st Embodiment of the resin coupling by this invention. It is a figure which shows the manufacturing method of the resin coupling by this invention. It is sectional drawing which shows 2nd Embodiment of the resin coupling by this invention. It is sectional drawing which shows 3rd Embodiment of the resin coupling by this invention. It is sectional drawing which shows 4th Embodiment of the resin coupling by this invention. It is a figure which shows the latter half part of the piping method of the resin tubes by this invention.

Explanation of symbols

(1) (2) (21) (31) Resin fitting
(5) (7) (22) (32) Body
(6) (8) (23) (24) (25) (33) (34) Cylindrical member

Claims (5)

  A resin joint used for forming a pipe using a tube made of a predetermined resin, wherein the hollow joint body is molded into a predetermined shape, and one end is welded to the joint body and the other end is A resin joint comprising: at least one cylindrical member protruding from the joint body, wherein the cylindrical member is made of a resin having a melt flow rate of 0.5 to 1.5 times the melt flow rate of the tube. .   The resin joint according to claim 1, wherein the joint body is an injection molded product or a cut product, and the cylindrical member is an extruded material.   The resin joint according to claim 1 or 2, wherein the joint body is made of PFA resin having a melt flow rate of 10 to 20 g / 10 min, and the cylindrical member is made of PFA resin having a melt flow rate of 1 to 5 g / 10 min.   When forming a pipe using a pipe forming tube made of a predetermined resin, the same resin tube as the pipe forming tube is cut to a predetermined length, and then one end of the cut tube is formed into a predetermined shape. A method for piping a resin tube, comprising: welding a hollow joint body molded into a hollow tube, and then welding the other end of the cut tube to one end of a tube for forming a pipe.   When welding one end of the cutting tube to the joint body, at least one member is rotated to weld the members together by frictional heat generated on the contact surfaces of both members, and the other end of the cutting tube is formed as a pipe 5. The method of piping a resin tube according to claim 4, wherein when welding to the tube, the end portions of both members are heated and melted and welded by butting the melted end portions together.

Images